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Space Science

SOHO Is Back 93

c4tp's friend writes "Space.com reports that SOHO (Solar and Heliospheric Observatory) is back and almost fully operational. The satellite should be able to transmit 98% of the data it was able to transport before an electric motor stuck disabling its high gain attenae in June (covered by Slashdot). The fix includes a 180 degree rotation of SOHO and use of another satellite dish transmitting the information via the Deep Space Network. SOHO will be out of order for about nine to sixteen days every three months."
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SOHO Is Back

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  • no longer, detect my home planet, will you.
  • OK (Score:4, Funny)

    by jabbadabbadoo ( 599681 ) on Friday July 18, 2003 @07:11AM (#6469591)
    SOHO - Semi Operational Heliospheric Observatory. Sick of it.
  • by pen ( 7191 ) on Friday July 18, 2003 @07:12AM (#6469592)
  • Deja vu? (Score:5, Interesting)

    by pen ( 7191 ) on Friday July 18, 2003 @07:19AM (#6469628)
    It looks like SOHO was already "nearly back in business [google.com] in 1998...

    Regardless of administrative crap, here are some nice shots of our by far biggest source of life energy [nasa.gov]!

    • It's gone down a couple of times before for various reasons. Through patients, effort, and some creative software they've always managed to bring it back to life.
    • ... our by far biggest source of life energy!

      Hmm... could you explain "source of life energy"? If you consider direct harnessing of sunlight, then solar power is a tiny fraction compared to the other sources. OTOH if you refer to both direct and indirect forms, then all sources of energy, including plant and animal food, coal, etc. are derived from solar energy. (except nuclear energy, but I can't see how you can call it "life energy" :-)

      • Well, that particular way of phrasing of it came from my love for Mother Earth, the Sun, and the Universe that we live in. (I am not pagan, as I don't subscribe to a religion, but I guess I look in a similar direction. And no, I don't believe to any political parties either.)

        But when you think about it, aside from nuclear power that you mentioned, all of our energy comes from the Sun. Just about every creature requires the Sun's warmth. Plants feed directly on the Sun's energy. Animals, whether sheep, beet

        • Errr... that should be "don't belong to any political parties" hehe
        • But when you think about it, aside from nuclear power that you mentioned, all of our energy comes from the Sun.

          If you think about it, even nuclear power comes from uranium which was created by previous stars that went supernova. So it's also solar in a roundabout way.
  • Hooray (Score:5, Funny)

    by Anonymous Coward on Friday July 18, 2003 @07:19AM (#6469629)
    Looks like nasa finally got that shipment of metric converter calculators i sent them
  • by FTL ( 112112 ) <slashdot@@@neil...fraser...name> on Friday July 18, 2003 @07:24AM (#6469656) Homepage
    It continually amazes me what ground control can do with damaged hardware. Galileo had an LED (part of the tape drive) which had burned out; but they managed to repair it. Voyager 2 had its entire OS replaced from half way across the solar system. A space telescope with a dead tracking system was revived using software to watch stars using the main camera. Sats with dead gyroscopes have been reactivated using jury-rigged torquer bars which interact with Earth's magnetic field. One communications sat used the Moon as an unscheduled slingshot to get it into the correct orbit after its main booster failed.

    So don't laugh when one of these upgrades goes wrong. Like one of the Vikings which was accidentally sent the command "switch off your reciever" while on the surface of Mars (it is still there, patiently waiting for the next order).

    • I wholeheartedly agree. However, Viking's still there, with it's batteries long dead...

      Wouldn't it be a hoot if, say, 50 years from now, a couple of astronauts found it, dusted it off, replaced the batteries, hit the master reset button (or whatever) and it sprang back to life!

      • I wholeheartedly agree. However, Viking's still there, with it's batteries long dead...

        Wouldn't it be a hoot if, say, 50 years from now, a couple of astronauts found it, dusted it off, replaced the batteries, hit the master reset button (or whatever) and it sprang back to life!


        Wouldn't it be even more of a hoot if it spontaneously and mysteriously started transmitting on its own? If they even told us about it, NASA would have a lot of questions.
      • > Wouldn't it be a hoot if, say, 50 years from
        > now, a couple of astronauts found it, dusted it
        > off, replaced the batteries, hit the master
        > reset button (or whatever) and it sprang back to life!

        Given the collapse of the Space Age in the US, I think it'd be a hoot if astronauts made it even halfway to the nearest (non-Earth) planet before I'm dead.

        --
        -JC
        http://www.jc-news.com/coding/SFi/
      • V'GER requires the information
    • Voyager 2 had its entire OS replaced from half way across the solar system.

      Too bad that was before /. existed. We have stories about someone's grandma switching to linux hitting the front page all the time, imagine the splash this would have caused ... oh wait ... voyager was before linux too, wasn't it? So it can't have been ... damn nevermind what I was saying

      :-P

    • If anyone has links to more details on these stories I'd be really interested. Specifically how the Viking accident happened.
    • I couldn't find any information on that... I did find that the USSR Phobos 1 had been told to turn off [solarviews.com] it's attitude thrusters, loosing the sattelite en-route...
    • Sats with dead gyroscopes have been reactivated using jury-rigged torquer bars which interact with Earth's magnetic field.

      SOHO originally had 3 gyroscopes, but they all broke after the deep-freeze in 1998. With new software, we can use the reaction wheels as gyroscopes (albeit much less sensitive ones).

    • It continually amazes me what ground control can do with damaged hardware. Galileo had an LED (part of the tape drive) which had burned out; but they managed to repair it.

      Galileo's biggest problem was perhaps its damaged main antenna. They had to use a low-gain antenna for the entire trip by greatly compressing the data using JPEG-like techniques. However, they also had to greatly limit its imaging, scrapping plans such as making time-lapse "movies" of Jupiter's weather.
  • by Anonymous Coward on Friday July 18, 2003 @07:27AM (#6469672)
    The Sun-watching SOHO spacecraft is back in full operational mode after a partial blackout period that raised serious concerns among space weather forecasters. The probe could survive until 2008, when a replacement probe could be launched SPACE.com has learned.

    Though limping a bit, SOHO is now able to resume meeting most of its original mission objectives thanks to creative engineering solutions, an elated mission official said.

    SOHO (Solar and Heliospheric Observatory) began having problems in early June. A stuck motor drive would not permit its high-gain antenna to move. The antenna is used for transmitting important pictures and data back to Earth, and it must be pointed toward the planet.

    No other set of satellites can produce the data provided by SOHO, scientists say.

    This week the spacecraft's orbit brought it into a favorable position and, as planned, engineers flipped the craft 180 degrees so its antenna could point toward Earth. SOHO orbits a gravitationally stable point in space, partway between Earth and the Sun, every six months.

    "Things are back in full operation," said Joe Gurman of the Solar Data Analysis Center at NASA's Goddard Space Flight Center.

    Gurman said in a telephone interview that despite continuing gaps in SOHO's ability to transmit, about 98 percent of the data required by space weather forecasters will be returned during the rest of the spacecraft's lifetime.

    That life has lasted more than seven years, even though SOHO was designed for a two-year mission with a possible three-year extension.

    "The actual scientific impact is pretty limited," Gurman said. "And we're really happy about that."

    When SPACE.com first reported the problem on June 19, officials said the result might be total blackout periods for several weeks each year. Space weather forecasters who rely on the data said it would gut their forecasts, which in turn are used by satellite operators and power companies to minimize risk of failure during strong solar storms. Even commercial television broadcasts and pager services would have been at greater risk for downtime if storms struck without warning.

    The SOHO team has proven resourceful, however.

    The probe entered an expected blackout period on June 27. Since then, officials have employed a slower backup antenna to transmit data. A creative solution was devised. Some data was recorded on board and then downloaded using high-speed transmissions -- through the backup antenna -- when time could be spared on large 70-meter dishes of NASA's Deep Space Network (DSN).

    SOHO does not normally use the high-capability DSN.

    SOHO officials will meet later today with the DSN team to discuss how much time they can get on the network. Gurman said beginning early next year the spacecraft's needs will find tough competition from a plethora of Mars missions that will also rely on the DSN.

    Meanwhile, a similar approach allows some data to be returned to a 34-meter dish when the DSN is not available.

    Full and normal operation resumed on July 14. Partial blackouts lasting between nine and 16 days will continue to occur every three months.

    "It is good to welcome SOHO back to normal operations, as it proves that we have a good understanding of the situation and can confidently work around it," said Stein Haugan, acting SOHO project scientist with the European Space Agency.

    Engineers expect the craft to endure. Barring catastrophe, SOHO could last until a similar probe, the Solar Dynamics Observatory (SDO), is launched, possibly in 2008.

    Gurman said SDO, if it goes up as planned, would be a 100-percent replacement for SOHO.

    Meanwhile, solar activity is lessening. An 11-year cycle peaked over the past two years and is ramping down to a low point that will come between 2005 and 2007.

    "I see no reason to believe we can't continue to operate in this fashion through the end of the solar cycle," Gurman said.

    SOHO is a joint project between NASA and the European Space Agency.ht
  • by ThePyro ( 645161 ) on Friday July 18, 2003 @07:31AM (#6469685)
    Now witness the firepower of this fully armed and operational observatory!
  • Great! (Score:5, Funny)

    by moehoward ( 668736 ) on Friday July 18, 2003 @07:50AM (#6469772)
    I love a happy ending.

    But the story could have used a bit more drama. And maybe even its own Aerosmith song.
    • Re:Great! (Score:5, Insightful)

      by ChuckDivine ( 221595 ) * <charles.j.divine@gmail.com> on Friday July 18, 2003 @08:12AM (#6469907) Homepage
      moehoward writes:
      I love a happy ending. But the story could have used a bit more drama. And maybe even its own Aerosmith song.

      I love a happy ending, too. And drama is terrific, too. But you don't want drama everywhere. SOHO is an observatory that performs a quite useful function for the human race. It's better for it to perform that function as well as it can. That probably means with as little drama as possible.

      Engineering and science can be part of something quite dramatic. Check out a mid 50s British film "The Dam Busters" for an illuminating look at real engineers involved in real drama. Or the Ron Howard film "Apollo 13" for a more modern look at engineers involved in high drama.

      But everyday engineering and science should avoid drama. Drama comes from unexpected events (e.g., Apollo 13's failures, natural catastrophe) and conflict (war, political campaigns, etc.). Society (as well as scientists and engineers) want technology to work, not provide drama -- unless that is a deliberate goal. Routine technology should not be dramatic. Dramatic events should not be routine.

      And hearty congratulations are in order for the people who got SOHO working again.

      • Ok. I see your point. But can you ask CNN to at least wrap the story on this undramatic ending with some Aerosmith in the background?

        Give me something here. It's a slow news summer. Shark attacks are down. And even the Kennedy's are relatively under control. I need a story that we can unfold and wrap up by Labor day.
        • Dude, NO story needs an Aerosmith song. I'm still pissed at Run-DMC for resurrecting their career. They were cool in the '70s but they haven't done anything but insipid trash since then. Instead of fading away into obscurity leaving us bittersweet memories of great songs like "Dream On" and "Kings and Queens", they have to "Pump" out crap like "Rag Doll", "Love in an Elevator", and "Just Push Play". No thanks, I'd much rather push Eject.
    • Re:Great! (Score:3, Funny)

      by rde ( 17364 )
      But the story could have used a bit more drama. And maybe even its own Aerosmith song.

      Drama? I've been following this story for ages courtesy of NASA's email bulletins. Now that SOHO's online again, I can start worrying about Mars Express.

      As for the song:

      Spacecraft floatin' with the comets in space
      And your lens pointin' up in the air
      Singin' hey what the hell
      Things ain't goin' too well
      The antenna's actions causin' a scare
      So we tried somethin' strange with the bot at Lagrange
      And we tried pointin' back at
  • The fix includes a 180 degree rotation of SOHO and use of another satellite dish transmitting the information via the Deep Space Network.

    Deep Space Network? Brings to mind UFO's and conspiracy theories. Or a linux server on Deep Space Nine!

    • by confused one ( 671304 ) on Friday July 18, 2003 @08:08AM (#6469872)
      Actually it's kind of misleading. They're using the low gain antenna now which, using the original uplink, was only capable of low bandwidth. Basically, it was for sending control commands, etc; not for transmitting back the images and other data. By using the big antennas in the deep space network, they increase the sensitivity on this end; and, they've worked out an algorithm (uploaded to the SOHO) which allows them to transmit the data collected back to Earth, using the low gain antenna for higher bandwidth.

      I bet the electrical engineers and software people missed a few nights sleep working this out...

      • [...]they've worked out an algorithm (uploaded to the SOHO)[...]

        No software changes were necessary; it simply had not been tried before.

        #standard disclaimer: I work for SOHO, but I don't speak for NASA or my employer.

  • by AtariAmarok ( 451306 ) on Friday July 18, 2003 @08:04AM (#6469839)
    This looks suspiciously boxy. For all we know, they have launched one of those shoeboxes [montreal.qc.ca] that can be used to observe the Sun safely during an eclipse.
  • NASA Amazes Me (Score:5, Insightful)

    by Ignorant Aardvark ( 632408 ) * <cydeweys@nospam.gmail.com> on Friday July 18, 2003 @08:25AM (#6469982) Homepage Journal
    I never cease to be amazed by all that NASA is capable. Time and time again they have had (understandable) glitches occur, because space is the most hostile environment. And time and time again they manage to come up with innovative solutions they can use to fix problems when the equipment is millions (or even billions) of miles away and cannot be touched. Voyager II was still transmitting data recently, and it's out of the solar system! How many other systems built three decades ago are still functioning? And do they have to contend with the harshest environment known to man?

    I commend NASA on their ingenuity and problem-solving skills. Microsoft, for instance, has so many bugs often times they'll just give up on problems where they even have physical access to the device and just tell you to "reinstall the OS"! NASA works under many more constraints and yet consistently manage to get the job done right. There's no other organization (governmental or otherwise) that I place as much trust in as NASA. They're working for all humankind and won't let anything get in their way.
    • "I never cease to be amazed by all that NASA is capable. Time and time again they have had (understandable) glitches occur, because space is the most hostile environment."

      When you get right down to it, space is not the problem. It is getting there, or getting back that is the problem (especially atmospheres). Once you get out into the void, things seem to work pretty well (at least until you leave space and try to enter another atmosphere, such as Mars)

      Voyager II was still transmitting data recently, an
      • What are you talking about? Temperature variations, radiation, power requirements vs supply. Just three of the (many) problems made far more complex by leaving our atmosphere. I do agree, though, that launch is the most difficult phase. It adds new problems like weight, vibration and size to the mix. All the above problems do, of course, exist when designing conventional aircraft. But they're far, far harder when designing a spacecraft.
      • When you get right down to it, space is not the problem. It is getting there, or getting back that is the problem (especially atmospheres). Once you get out into the void, things seem to work pretty well (at least until you leave space and try to enter another atmosphere, such as Mars)

        Getting through the atmosphere is indeed dangerous. But I think you underestimate how harsh an environment space really is. It's full of micrometeorites that will tear through your craft if you're travelling fast, and the radiation is killer, because you aren't shielded by the atmosphere. Solar flares could easily put you out of commission too - that's why satellites include technology originally developed during the Cold War to shield against EMP from nuclear blasts. And the temperature gradient is killer too - hundreds of degrees on the side of the craft facing the Sun, and near absolute zero on the other side. If you don't have good heat dissipation systems you're fried (quite literally).

        Again, this is not near as harsh on NASA's equipment as our own atmosphere is. Once the stuff gets into space safe and clear, it seems to run pretty well precisely because space is pretty safe when it comes to danger to the craft.

        99% of the things in the Earth's atmosphere do a lot better in the atmosphere than in space. I don't think you appreciate what amount of engineering goes into even the simplest of satellites that are put into space. And once you put things up there, maintenances is, for the most part, out of the question. You better make sure you get it right, because you can't just send out a maintenance team to fix things up every year like you could with something installed on the ground.

        Let me sum up with a final comment: I'm glad the parent was only modded up interesting, not informative, because it's quite wrong.
        • Do you know how many craft are lost on launch, reentry, or planetfall compared to craft that are lost just moving through space?

          I do not know for sure, but I suspect that the latter total is lower. Certainly it is true for the shuttles. If this is true for spacecraft in general, then the parent was not "quite wrong": space is indeed less of a danger for spacecraft than other environments.
          • Spacecraft lost on launch are often the result of a launch vehicle failure, rather than a spacecraft failure. Some spacecraft do fail just after launch (during the deployment sequence), but this is a function of the "infant mortality" phenomenon well known to reliability engineers - i.e. it's usually not an environmental factor but a design fault.

            Spacecraft do not tend to reenter the Earth's atmosphere. Those that do are typically being disposed of at the end of their life, so failure is really a meaningl

    • Re:NASA Amazes Me (Score:3, Interesting)

      by ChuckDivine ( 221595 ) *

      You haven't been paying attention the past several years, have you?

      Consider:

      • Two space shuttles lost. A poor design, dishonestly sold, a marked failure. Routine, cheap access to space it isn't. Successor vehicles aren't doing too well, either.
      • Hubble trouble -- not because "space is hard" but because people didn't bother to correctly test the observatory on the ground.
      • Probes crashing into Mars because one part of the team working in metric, another in English units.

      These are just some high pr

    • Re:NASA Amazes Me (Score:2, Informative)

      by CaptKilljoy ( 687808 )
      I think you're overstating the case. This succeeded because of ingenuity and innovation, but also because they spend a lot of money and time on the design process to guarantee reliability and flexibility (since they can't send people up for repair) and because they are using hardware/software that are much less complex than a PC/consumer software. (Voyager II's computer is dirt-simple.)

      This success doesn't reflect anyting about consumer HW/SW because it's at an entirely different place in the good/fast/ch

  • Making Trouble (Score:3, Interesting)

    by Betelgeuse ( 35904 ) on Friday July 18, 2003 @08:49AM (#6470117) Homepage
    The thing about this is that the SOHO engineers really made more trouble for themselves. When they first discovered the possible problem with the motor on the high gain antenna, it was in a relatively good position (i.e. they would have had to roll the telescope every three months, but never would have lost any data). Then, just to "test out" to see if they could get the motors to work, they moved the high gain antenna to its two extremes. Of course, the antenna got stuck near one of its extreme positions. Don't you just hate it when people can't leave well enough alone? :-)

    Also, I find it entertaining that a standard way to try to fix something on a space-based instrument is to shake the entire instrument. Seems rather low-tech, but they did it both with SOHO along with other satelites at one point or another.
    • Re:Making Trouble (Score:3, Informative)

      by teridon ( 139550 )
      Then, just to "test out" to see if they could get the motors to work, they moved the high gain antenna to its two extremes. Of course, the antenna got stuck near one of its extreme positions.

      I don't know where you got that disinformation! It is currently near the center position.

      The antenna CAN be moved (it is NOT stuck, as we found out during testing), but with a high risk that it could get stuck permanently. However, the antenna beam pattern needed to be tested, *in flight*, so that we could optimize i

  • by Anonymous Coward on Friday July 18, 2003 @08:54AM (#6470137)

    ... why are space weather forecasters, satellite operators, and power companies relying on a satellite which is already two years past its most optimistic scheduled lifespan?

    I was really bugged by this quote:

    Space weather forecasters who rely on the data said it would gut their forecasts, which in turn are used by satellite operators and power companies to minimize risk of failure during strong solar storms. Even commercial television broadcasts and pager services would have been at greater risk for downtime if storms struck without warning.

    Kudos to NASA and ESA for keeping SOHO flying, and I hope they continue to do so. But if the private sector depends critically on SOHO output, perhaps they should have their own bird flying by now, rather than waiting for the next solar observer scheduled to fly by 2008. If this is considered a mission vital to the overall public good (like, for example, NOAA's GOES satellites), why are we hearing about this now rather than in 2001 when SOHO was scheduled to expire?

    If SOHO goes quiet and your business is affected, don't complain that NASA et al are falling down on the job -- launch your own satellite!

    • ... why are space weather forecasters, satellite operators, and power companies relying on a satellite which is already two years past its most optimistic scheduled lifespan?
      because Congress (and various European governments) doesn't want to pay for a new one.
    • why are space weather forecasters [...] relying on a satellite [...] two years past its [...] lifespan?

      SOHO was launched at the end of 1995 and arrived in its orbit in mid-1996. The mission was originally scheduled to end in 1998. So we are now 5 years past its originally planned mission.

      But to answer your question -- there is currently no other spacecraft that could do SOHO's job. However, there are plans for a "Solar Dynamics Observatory (SDO)" [nasa.gov], part of the "Living with a Star" [nasa.gov] program. After it lau

  • by marcel-jan.nl ( 647348 ) on Friday July 18, 2003 @08:58AM (#6470165) Homepage
    The problem with SOHO is, that everyone has grown rather dependent on, what originally was a scientific, not an operational mission. It has now become a single point of failure in the gathering of important space weather forecasting data.

    Space.com recently had an article [space.com] about this. Without the constant stream of SOHO data, "it isn't too far off the mark that our forecasting methodology would revert back to the way it was many years ago," Joseph Kunches Chief, Space Weather Operations at the Space Environment Center told SPACE.com. "So without it for a little while...well, you keep your fingers crossed. You hope the Sun doesn't know," he said.
  • Odd.... (Score:5, Funny)

    by NanoGator ( 522640 ) on Friday July 18, 2003 @10:07AM (#6470807) Homepage Journal
    They just got back the last bit of data before the antenna was jammed. They picked up the faint outline of.... a Winnebago.
  • Seriously, there must be thousands.

    Example:
    I was reading this article about SOHO (SOlar and Heliospheric Observatory) in my SOHO (Small Office Home Office) while this SOHO (SOrority wHOre) was blowing me.

    (Yes I am a democrat).
  • SOHO = Small Office, Home Office

    http://www.acronymfinder.com/af-query.asp?Acrony m= soho&Submit=Acronym

  • by teridon ( 139550 ) on Friday July 18, 2003 @02:14PM (#6473187) Homepage
    SOHO does not normally use the high-capability DSN.

    This is incorrect. SOHO exclusively uses the DSN, but normally needs only 26-meter antennas. However, when downlinking using the "backup" low-gain antenna (which is omnidirectional), the 26-meter dish does not have enough gain to lock on telemetry. When using larger dishes, downlink is possible -- but the bit rate might be limited. For a 34-meter dish, SOHO can downlink at 56 kbps. For a 70-meter dish, SOHO can downlink at its normal rate, 256 kbps.

    The problem is, time on the larger dishes is hard to come by. When SOHO can't get time on a larger dish during the "blackout" period, it can't downlink. There are only 3 70-meter dishes in the DSN; most of the time another mission further out in space is using them.

  • Inventiveness (Score:3, Insightful)

    by phliar ( 87116 ) on Friday July 18, 2003 @02:37PM (#6473440) Homepage
    Sure, there's a lot of complaining about all the stupid things they do, with their quaint imperial vs. metric problems, astigmatism, etc. etc. But there's also creative and cool things they do with malfunctioning remote probes. Fault tolerance on the other side of millions-of-miles distances working with milliwatts of energy and absurdly low bandwidths, that's what I call cool. More tinkerers and less bureaucrats (and less obsession with a manned Shuttle program) is what NASA needs.
  • I hope Nasa figures out ways to have remote robotic arms with tools to repair complicated probes. Those Mars rovers are fairly likely to encounter mechanical problems. They might require a "space bobby-pin" of sorts.

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